Drum venting device



Oct. 31, 1950 H. BIRKENSTEIN, JR 2,523,207

DRUM VENTING DEVICE Filed Nov. 15, 1945 Patented Oct. 31, 1950 UNITEDSTATES ATENT oFFics 3 Claims. I

This invention relates to a venting device. More particularly myinvention pertains to a vent forming a part of a rotating drumcontaining gas-evolving liquids.

Revolving receptacles such as drums are commonly used in the processingindustries for the treatment of a large variety of materials. Frequentlyit is desirable to carry out the treatment within the revolving drumunder hydraulic pressure conditions. whenever one desires to hasten thereaction taking place within the drum. When materials are treated withliquid reagents in such revolving drums under conditions wherein duringthe treatment there is evolved volatile or gaseous material, it becomesnecessary to provide a means for venting or expelling such gases inorder to avoid the creation of dangerous over-pressures. This isparticularly true when the process involves the treatment of materialsin a rotating drum with reagent liquors which are under hydraulicpressure. Under such processing conditions it is important to provideefficient means for eliminating any gases evolved during the action ofthe reagent liquor within the revolving drum. The conventional safetyvalve does not provide the proper solution tosuch a problem. This isbecause such safety valves would sometimes be in communication with thegas zone in the revolving drum and at other times with the reagentliquor zone, with the result that there would alternately be vented bothgas and reagent liquor with consequent undesirable losses of reagentliquor.

Accordingly I provide a novel form of venting means which isparticularly suitable for rotating drums containing gas-evolving reagentliquors. As one example of the use to which my venting device may beput, reference is made to my copending application Serial No. 584,857,filed March 26, 1945, now abandoned, of which the present application isa continuation-in-part.

One of the objects of the present invention is to provide an efiicientmeans for venting volatile. or gaseous material from a, rotating closedreceptacle substantially filled with liquid reagents.

A further object of this invention is to provide a means for ventinggases created during theliquid processing of materials in a rotatingreaction chamber.

A still further object of the invention is to provide a means forcontinuously expelling evolved gases from a rotating treating drumsubstantially filled with reagent liquor. v,

Another object of my invention is to provide This is particularly true ameans for continuously venting evolved gases from a rotating drum whichis filled with reagent liquor wherein the latter is under hydraulicpressure.

Another object of my invention is to provide a means for continuouslyventing volatile matter from a rotating treating drum which is filledwith low boiling volatile solvents and which is under hydrostaticpressure.

Other objects and advantages will appear, expressed or implied, from thefollowingdescription of the present invention.

Referring to the drawings,

Fig. 1 is a diagrammatic front view of a rotatable drum to which m novelventing device is adapted; and

Fig. 2 is a side-elevational view of the same apparatus.

In one form of this invention the apparatus consists of a rotatable drum8 of any conventional construction. The drum is horizontally supportedfor rotation on the journals 23, and is provided with any type ofappropriate mechanical means for rotation during processing. Themechanical means best shown in Fig. 2 consists of the belt 2 5 driven bya suitable prime mover (not shown) and contacting the tire 25. The inletpipe ii] enters the drum coaxially with one of the journals 23 and isequipped with the control valve ii for feeding of reagent liquor intothe revolving drum. The pump is connected to the water pipe 86 providesmeans for furnishing superatmospheric or hydrostatic pressure on theliquor in the drum. The valve H is utilized for controlling thehydraulic pressure within the drum. An outlet valve 2| is provided foremptying the drum when desired. The drum 8 has a door 9 equipped withlocking means I 2 for securing the door tightly to the drum duringoperation.

The venting means of my invention comprises an inverted substantially'U-shaped conduit 22 rigidly attached to the outer periphery of the drum5 through the medium of a flange 38. One leg of the U is, as shown,shorter than the other,

the longer leg being attached to the hollow shaft.

3i by insertion within an aperture 32 in the pe riphery of the shaft,being engaged therewith by a threaded or pressed fit for fluidtightness.

The shaft 3! is, substantially cylindrical in form and is secured to thedrum 8 by the plurality of bolts 33 passing through the flange 34-, theend wall of the drum, and the reinforcing plate 35. A central aperture36 is in fluid communication with the conduit 22 and the stack M, therebeing provided at the outboard end of the shaft 3] a gland 31 andpacking 38 to form a stufiing box of conventional construction, therebypermitting rotation of the shaft, including the stuifing box, about thefixed stack E4. The stack 14 is equipped with the control valve l3 andextends vertically to a height suflicient to hold a head of fluidcapable of counterbalancing the hydraulic pressure within the drum.

A pressure gauge [8 is mounted on the drum periphery indicates thehydraulic pressure within the drum.

In Fig. 2 the drum is indicated as substantially filled with liquor 20and having the gas space 4|. As the drum rotates, the gaseous materialwill enter the pipe 22, which in turn delivers the same to the stack.

The following will illustrate the operation of my apparatus. Therotatable drum 8 is so positioned that the door 9 thereon facesupwardly, and the drum is filled through inlet pipe I and valve H withthe quantity of desired reagent liquor. The material to be treated bythe reagent liquor is then introduced through the door 9. The door isthen replaced and the locking means l2 securing it to the drum 8 aredrawn up tightly. The exhaust valve 13 in the stack I4 is then openedand a hydraulic pressure applied on the reagent liquor within the drumby means of the pump l5. This hydraulic pressure may be brought about byeither causing the pump l to force water through the water pipe 16 intothe reagent liquor in the drum, or the pump may be used to force anyother kind of liquid into the drum, depending upon the nature of thereagent liquor which is being handled. Thus if the drum is processingmaterials with immiscible solvent liquors such as carbon tetrachloride,etc., then the same type of liquor would be used in conjunction with thepump I5 for applying the necessary hydrostatic pressure in the drum 8.

The drum is then set in motion and is allowed to slowly rotate, usuallyat the rate of about 3 to 4 R. P. M. During the treatment of thematerials within the drum with the desired reagent liquor, any evolvedgases or vapors generated by the processing reaction will becontinuously and eificiently vented by my venting device. These gases orvapors will be carried through the U-shaped conduit 22 by means of thefluid connection between the reagent liquor in the drum and the aperture32 in the conduit. The liquor with the contained gases or vapors willthen enter the stack 5 stack, the liquid will rise to a heightcorresponding to the head of fluid which is suflioient to counterbalancethe hydraulic pressure within the drum. The length of the stack Itextends beyond such height. the liquid will pass through this fluid headand be vented into the air. This venting eifect takes placeintermittently during the operation of the drum. That is to say, as thedrum rotates venting will occur as the opening of the conduit 22 ispassing the gas zone. When the reaction is complete, valve [9 is closedand the reagent liquor within the drum discharged through valve 2!. Thetreated material is then removed through door 9 and the drum is readyfor another batch.

Where my apparatus is used for the liming of hides, the reagent liquorwould be a mixture of water, lime, and sodium polysulphide, and the rawmaterial would be wet, hairy hides. The evolved gas in this instance ishydrogen sulphide.

Upon entering this Any gases or vapors within This gas would becontinuously vented by my apparatus during the liming of the hides.Sometimes the sodium polysulphide in the hide liming treatment isreplaced by dimethylamine. In this case ammonia gas and dimethylaminevapors would be evolved during the liming treatment. These gaseousmaterials are readily vented and removed by my drum venting device.

My venting device for rotating processing drums is not limited to theuse of the particular chemicals mentioned in the above example nor tothe particular industry, namely, the hide-treating industry, mentionedin this example. The venting device is applicable to any treatment ofmaterials in-a rotating drum under conditions wherein the rotating drumcontains reagent liquor which evolves gaseous or volatile material. Anexample of the use of my venting device for the treatment of materialwith volatile liquid reagents is the dry-cleaning of textile material.In an ordinary dry-cleaning process, textile material, such as suits,dresses, etc., is placed in a revolving drum and the drum is then filledwith dry-cleaning liquor, which usually consists of highly volatileliquid solvents such as carbon tetrachloride, propylene dichloridesolvent naphtha, etc. These dry-cleaning solvents readily form largeamounts of vapors which tend to build up pressure within the revolvingdrum. By means of my venting device, any vapors of the dry-cleaningsolvents which are formed during the agitation of the textile materialwith the dry-cleaning solvents in the revolving drum can be readilyvented through the vent pipe l4, and by means of suitable connectionsthese solvent vapors can be led to a condensing means and therebyrecovered for re-use.

There are numerous other processes wherein gases or vapors are formedduring the treatment of raw materials with reagent liquors in revolvingdrums which may or may not be under hydrostatic pressure. Examples arethe bleaching of textile materials with sulphur dioxide-evolving reagentliquors such as sodium bisulphite liquors, the sulphur dioxide bleachingof foods such as cherries, etc., and the bleaching of paper pulp bymeans of chlorine or sulphur dioxide. Other examples are thechlorination of starch liquors and metallurgical operations involvingthe use of chlorine or other gaseous chemical reagents for theextraction of metals, such as copper, lead, zinc, etc. Another exampleis the de-tinning of iron plate coated with tin by means of chlorine. Afurther example is the neutralization of acidic material with soda ashor sodium bicarbonate with accompanying production of carbon dioxidegas. In all of the above instances there is a need for an efficientgas-venting mean wherever the process is carried out in a rotating drum,particularly when the process conditions are such that the reagentliquor in the rotating drum is under hydrostatic pressure. For all ofthese conditions my drum venting device offers an efiicient means fordisposing of any evolved gaseous material.

My invention may be modified in many other ways, and I do not wish to belimited to the details shown and described.

' I claim:

1. An apparatus of the type suitable for treating hides which comprisesa closed drum mounted for rotation upon a horizontal axis, and ventingmeans for the discharge of gases from said drum during its rotationwithout substantial loss of liquid therefrom despite its being almostcompletely filled with liquid which comprises a gasconducting pipecommunicating with the interior of the drum through the lateral wallthereof, a hollow trunnion not in communication with the interior of thedrum but adapted to rotate coaxially therewith, said gas-conducting pipebeing in open communication with said hollow trunnion, and a verticalgas-discharge standpipe freely vented to the atmosphere and in directcommunication with the interior of said hollow trunnion and of a heightsufficient to maintain a liquid column asserting a static liquidpressure at least equal to the pressure existing within the drum,whereby gas escaping from the interior of the drum through saidgas-conducting pipe and hollow trunnion may bubble upwardly through saidstandpipe and escape to the atmosphere.

2. An apparatus for the liquid processing of materials in Which gasesare evolved which comprises a drum mounted for rotation about asubstantially horizontal axis, a hub-member supporting said drum andhaving a passageway extending thereon, a vent pipe carried by said drumcommunicating with said passageway and opening into said drum at a pointremoved from the axis of rotation thereof, and an upwardly extendingstandpipe freely vented to the atmosphere also in communication withsaid passage way whereby gases evolved within said drum are vented fromthe drum through said vent pipe, said passageway and said standpipe.

3. An apparatus for the liquid processing of materials in which gasesare evolved which comprises a cylindrical drum mounted for rotationabout a substantially horizontal axis, a hub member supporting said drumand having a passageway and stufiing box therein, a vent pipe carried bysaid drum communicating with said passageway and said stufiing box andopening into said drum at a point adjacent the periphery thereof, and anupwardly extending standpipe freely vented to the atmosphere also incommunication with said passageway whereby gases evolved within saiddrum are vented from the drum through said vent pipe, said passagewayand stuffing box and said standpipe.

HARRY BIRKEN STEIN JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 536,019 Durio Mar. 19, 1895906,816 Nicolson Dec. 15, 1908 1,338,307 Krouse Apr.'27, 1920 2,374,247Thaxton Apr. 24, 1945 2,397,268 Jorgenson Mar. 26, 1946 Certificate ofCorrection Patent No. 2,528,207 October 31, 1950 HARRY BIRKENSTEIN, JR.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows:

Column 4, line 19, for the Word material read materials; column 5, line24, for thereon read therein;

and that the said Letters Patent should be read as corrected above, sothat the same may conform to the record of the case in the PatentOflice. Signed and sealed this 2nd day of January, A. D. 1951.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

